HILO, Hawaii — A sharp-eyed teenager on a helicopter tour over a volcano spotted a man who had vanished during a late-night hike across desolate lava fields days earlier.

Gilbert Dewey Gaedcke III, 41, of Austin, Texas, was dehydrated but apparently all right when he was found Friday after surviving five days in the heat, lost amid acres of black volcanic rock.

Gaedcke’s rented car had been found earlier at the end of a road near an old lava flow bordering the east side of the 333,000-acre Hawaii Volcanoes National Park.

Frantic family members rushed from Texas to Hawaii, making public pleas for any information.

Fire crews and rangers searched for days — on foot and on horseback. Helicopters buzzed the area, but there was no sign of Gaedcke until he was spotted by 15-year-old Peter Frank.

“It was the only thing like that out there,” said Frank, of Pasadena, Calif. “As we got closer, we realized it was man.”

The helicopter pilot flew the family back and then returned for Gaedcke, who was recuperating at a private home on Saturday. The rescued man had words of gratitude for the teenager who spotted him from the helicopter.